Many different forms of solar heaters have been heretofore provided for the purpose of heating a working liquid. However, most stationarily supported solar heaters operate at extremely low efficiency during the first three or four hours after sunrise and the three or four hours preceding the setting of the sun and enjoy reasonable efficiency only during the several hours bridging the time at which the sun is at its highest point. Examples of various forms of solar heaters designed to enjoy greater efficiency throughout the entire period between sunrise and sunset are disclosed in U.S. Pat. Nos. 2,455,834, 2,636,129, 2,872,915, 2,918,023 2,993,125, 3,125,091 and 3,391,688.
However, these previously patented solar heaters do not provide maximum efficiency with relatively simple structure which may be produced at a low cost.